day-21-part2.rb

require 'benchmark'
require 'stringio'
require "enumerator"

file_content = File.read(File.join(__dir__, 'input.txt'))
start_a, start_b = file_content.scan(/\d+$/).map(&:to_i)



class Player
  attr_accessor :score

  def initialize(start, name)
    @name = name
    @space = start
    @score = 0
  end

  def play(values)
    @space = (@space + values.sum - 1) % Game::MAX_SPACE + 1
    @score += @space
    # not 0 based so shift forth and back the num
    puts "#{@name}: #{@space} (#{@score})"
  end

  def wins?
    @score >= Game::MAX_SCORE
  end
end

class Game
  MAX_SPACE = 10
  MAX_SCORE = 1000

  def initialize(start_a, start_b)
    @die = DETERMINISTIC_DIE
    @rounds = 0
    @p_a = Player.new(start_a, "Player A")
    @p_b = Player.new(start_b, 'Player B')
  end

  def play
    until @p_a.wins? || @p_b.wins?
      @rounds += 1
      @p_a.play(3.times.collect{ @die.next[1] })
      break if @p_a.wins?

      @rounds += 1
      @p_b.play(3.times.collect{ @die.next[1] })
      break if @p_b.wins?
    end

    min_score = [@p_a.score, @p_b.score].min
    rolls = @die.peek[0] - 1


    result = min_score * rolls
    puts "result #{result}"
  end
end

def create_die(start_side = 0, start_rolls = 0)
  Enumerator.new do |yielder|
    side = start_side
    rolls = start_rolls
    
    loop do
      rolls += 1
      side = 0 if side >= 100

      side += 1
      yielder << {rolls: rolls, side: side, die: create_die(side, rolls)}

    end
  end
end


initial_die = create_die
a = [0, 0]
b = [0, 0]

dies = initial_die.take(3).to_a
die1 = dies[0][:die]


puts "ok"